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diff --git a/docs/quick_tutorial/debugtoolbar.rst b/docs/quick_tutorial/debugtoolbar.rst index 90750c633..2607c83f2 100644 --- a/docs/quick_tutorial/debugtoolbar.rst +++ b/docs/quick_tutorial/debugtoolbar.rst @@ -4,111 +4,129 @@ 04: Easier Development with ``debugtoolbar`` ============================================ -Error-handling and introspection using the ``pyramid_debugtoolbar`` -add-on. +Error handling and introspection using the ``pyramid_debugtoolbar`` add-on. + Background ========== -As we introduce the basics we also want to show how to be productive in -development and debugging. For example, we just discussed template -reloading and earlier we showed ``--reload`` for application reloading. +As we introduce the basics, we also want to show how to be productive in +development and debugging. For example, we just discussed template reloading, +and earlier we showed ``--reload`` for application reloading. + +``pyramid_debugtoolbar`` is a popular Pyramid add-on which makes several tools +available in your browser. Adding it to your project illustrates several points +about configuration. -``pyramid_debugtoolbar`` is a popular Pyramid add-on which makes -several tools available in your browser. Adding it to your project -illustrates several points about configuration. Objectives ========== -- Install and enable the toolbar to help during development +- Install and enable the toolbar to help during development. + +- Explain Pyramid add-ons. -- Explain Pyramid add-ons +- Show how an add-on gets configured into your application. -- Show how an add-on gets configured into your application Steps ===== -#. First we copy the results of the previous step, as well as install - the ``pyramid_debugtoolbar`` package: +#. First we copy the results of the previous step. + + .. code-block:: bash + + cd ..; cp -r ini debugtoolbar; cd debugtoolbar - .. code-block:: bash +#. Add ``pyramid_debugtoolbar`` to our project's dependencies in ``setup.py`` as a :term:`Setuptools` "extra" for development: - $ cd ..; cp -r ini debugtoolbar; cd debugtoolbar - $ $VENV/bin/python setup.py develop - $ $VENV/bin/easy_install pyramid_debugtoolbar + .. literalinclude:: debugtoolbar/setup.py + :language: python + :linenos: + :emphasize-lines: 10-16, 20-22 -#. Our ``debugtoolbar/development.ini`` gets a configuration entry for - ``pyramid.includes``: +#. Install our project and its newly added dependency. + Note that we use the extra specifier ``[dev]`` to install development requirements and surround it and the period with double quote marks. - .. literalinclude:: debugtoolbar/development.ini - :language: ini - :linenos: + .. code-block:: bash -#. Run the WSGI application with: + $VENV/bin/pip install -e ".[dev]" - .. code-block:: bash +#. Our ``debugtoolbar/development.ini`` gets a configuration entry for ``pyramid.includes``: - $ $VENV/bin/pserve development.ini --reload + .. literalinclude:: debugtoolbar/development.ini + :language: ini + :linenos: + +#. Run the WSGI application with: + + .. code-block:: bash + + $VENV/bin/pserve development.ini --reload + +#. Open http://localhost:6543/ in your browser. + See the handy toolbar on the right. -#. Open http://localhost:6543/ in your browser. See the handy - toolbar on the right. Analysis ======== -``pyramid_debugtoolbar`` is a full-fledged Python package, -available on PyPI just like thousands of other Python packages. Thus we -start by installing the ``pyramid_debugtoolbar`` package into our -virtual environment using normal Python package installation commands. - -The ``pyramid_debugtoolbar`` Python package is also a Pyramid add-on, -which means we need to include its add-on configuration into our web -application. We could do this with imperative configuration in -``tutorial/__init__.py`` by using ``config.include``. Pyramid also -supports wiring in add-on configuration via our ``development.ini`` -using ``pyramid.includes``. We use this to load the configuration for -the debugtoolbar. - -You'll now see an attractive button on the right side of -your browser, which you may click to provide introspective access to debugging -information in a new browser tab. Even better, if your web application -generates an error, -you will see a nice traceback on the screen. When you want to disable -this toolbar, no need to change code: you can remove it from -``pyramid.includes`` in the relevant ``.ini`` configuration file (thus -showing why configuration files are handy.) - -Note injects a small amount of html/css into your app just before the closing -``</body>`` tag in order to display itself. If you -start to experience otherwise inexplicable client-side weirdness, you can shut -it off by commenting out the ``pyramid_debugtoolbar`` line in -``pyramid.includes`` temporarily. +``pyramid_debugtoolbar`` is a full-fledged Python package, available on PyPI +just like thousands of other Python packages. Thus we start by installing the +``pyramid_debugtoolbar`` package into our virtual environment using normal +Python package installation commands. + +The ``pyramid_debugtoolbar`` Python package is also a Pyramid add-on, which +means we need to include its add-on configuration into our web application. We +could do this with imperative configuration in ``tutorial/__init__.py`` by +using ``config.include``. Pyramid also supports wiring in add-on configuration +via our ``development.ini`` using ``pyramid.includes``. We use this to load the +configuration for the debugtoolbar. + +You'll now see an attractive button on the right side of your browser, which +you may click to provide introspective access to debugging information in a new +browser tab. Even better, if your web application generates an error, you will +see a nice traceback on the screen. When you want to disable this toolbar, +there's no need to change code: you can remove it from ``pyramid.includes`` in +the relevant ``.ini`` configuration file (thus showing why configuration files +are handy). + +Note that the toolbar injects a small amount of HTML/CSS into your app just +before the closing ``</body>`` tag in order to display itself. If you start to +experience otherwise inexplicable client-side weirdness, you can shut it off +by commenting out the ``pyramid_debugtoolbar`` line in ``pyramid.includes`` +temporarily. + +Finally we've introduced the concept of :term:`Setuptools` extras. +These are optional or recommended features that may be installed with an "extras" specifier, in this case, ``dev``. +The specifier is the name of a key in a Python dictionary, and is surrounded by square brackets when invoked on the command line, for example, . +The value for the key is a Python list of dependencies. .. seealso:: See also :ref:`pyramid_debugtoolbar <toolbar:overview>`. -Extra Credit + +Extra credit ============ -# Why don't we add ``pyramid_debugtoolbar`` to the list of - ``install_requires`` dependencies in ``debugtoolbar/setup.py``? +#. We added ``pyramid_debugtoolbar`` to the list of ``dev_requires`` dependencies in ``debugtoolbar/setup.py``. + We then installed the dependencies via ``pip install -e ".[dev]"`` by virtue of the Setuptools ``extras_require`` value in the Python dictionary. + Why did we add them there instead of in the ``requires`` list? -# Introduce a bug into your application: Change: +#. Introduce a bug into your application. Change: - .. code-block:: python + .. code-block:: python - def hello_world(request): - return Response('<body><h1>Hello World!</h1></body>') + def hello_world(request): + return Response('<body><h1>Hello World!</h1></body>') - to: + to: - .. code-block:: python + .. code-block:: python - def hello_world(request): - return xResponse('<body><h1>Hello World!</h1></body>') + def hello_world(request): + return xResponse('<body><h1>Hello World!</h1></body>') - Save, and visit http://localhost:6543/ again. Notice the nice - traceback display. On the lowest line, click the "screen" icon to the - right, and try typing the variable names ``request`` and ``Response``. - What else can you discover? + Save, and visit http://localhost:6543/ again. + Notice the nice traceback display. + On the lowest line, click the "screen" icon to the right, and try typing the variable names ``request`` and ``Response``. + What else can you discover? |